A Common Channel Signaling (CCS) network is a high speed packet switch network that is used for trunk signaling and for the provisioning of enhanced network services such as 800 Service, Alternate Billing Services (ABS), Private Virtual Networks (PVN), Area Wide Centrex, etc. CCS is provided in accordance with specifications for Signaling System 7 (SS7) protocol.
As illustrated in FIG. 1, the CCS network, generally indicated at 10, consists of the following Network Elements: CCS switching offices which are stored program controlled switching systems Signaling Transfer Points (STP), and Service Control Points (SCP). The CCS Switching Office is the CCS network interface to the voice network. It is capable of generating and receiving CCS messages for call set-up. CCS SO's equipped with additional software capable of formulating queries for transaction based services are called Service Switching Points (SSPs) and access other nodes in the CCS network via signaling links to Signaling Transfer Points (STPs). The STPs are specialized packet switches that serve as intermediate message transport switches. The STP performs routing for trunk signaling and global title translation for enhanced services. The SCP is the network component which provides the enhanced services mentioned above.
Referring still to FIG. 1, the SEAS.TM. (a trademark of the assignee of the present application) system is the primary support system that is responsible for the administration of the CCS network and the engineering of its components. Thorough administration of the CCS network requires close surveillance of CCS activity and careful provisioning and management of CCS related components. CCS related components include, where applicable, buffers, processors, and data buses, and the signaling links and linksets they serve. Engineering of the CCS network requires analysis of collected traffic and performance measurements for the purpose of sizing the various CCS related components.
The specific administrative features the SEAS system provides are Recent Change and Verification (RC&V), Network Management, Surveillance for Maintenance, and Network Monitoring and Surveillance for Administration. The specific engineering features the SEAS system provides are data validation and summarization and busy hour determination among other functions performed by Data Analysis. Supporting both the administrative and engineering operations are Data Collection and a Network Configuration Records Base (NCRB).
Routing and translation tables at the STP facilitate the switching of SS7 messages. For those STPs able to switch inter-network traffic, a set of screening tables support the discrimination of allowed messages. Recent Change messages update those routing tables as needed to effect changes in routing and/or screening patterns. The Verify capability enables synchronization of the routing tables with the "ineffect" copy kept at the SEAS system.
In order to engineer and administer the CCS network, the SEAS system collects various types of measurement data from the network components. The collected data allows users to monitor service levels on a near-real-time basis using thresholding capabilities provided with the SEAS Network Monitoring and Surveillance for Administration feature. Different types of measurement data are collected at different intervals, e.g. traffic and performance measurements at 30 minute intervals and network management data at 5 minute intervals.
Recent outages in Common Channel Signaling (CCS) Networks have raised questions about their survivability. Analyzing outage data is important for recognition and avoidance of CCS problems.